Merge ce6939ce4090aa41861cd93daccce4b68f891b25 into 63dd3e60cab89c27fb66bce1423bd268d52abad1

Co-authored-by: Bo-Yi Wu <appleboy.tw@gmail.com>

docs/doc.md

@@ -9,6 +9,7 @@
   - [Using GET, POST, PUT, PATCH, DELETE and OPTIONS](#using-get-post-put-patch-delete-and-options)
   - [Parameters in path](#parameters-in-path)
   - [Querystring parameters](#querystring-parameters)
+  - [Retrieving the path of a registered handler](#retrieving-the-path-of-a-registered-handler)
   - [Multipart/Urlencoded Form](#multiparturlencoded-form)
   - [Another example: query + post form](#another-example-query--post-form)
   - [Map as querystring or postform parameters](#map-as-querystring-or-postform-parameters)
@@ -184,6 +185,29 @@ func main() {
 }
 ```
 
+### Retrieving the path of a registered handler
+
+Once a handler is registered with the router, you can retrieve its path with the `PathFor` method:
+
+```go
+func main() {
+  // Creates a gin router with default middleware:
+  // logger and recovery (crash-free) middleware
+  router := gin.Default()
+
+  getUser := func(c *Context) {
+    // Handle the GET request.
+  }
+  router.GET("/users/:name", getUser)
+  path := router.PathFor(getUser, ":name", "gopher")
+
+  print(path) // Prints /users/gopher
+
+  router.Run()
+}
+router := gin.Default()
+```
+
 ### Multipart/Urlencoded Form
 
 ```go

gin.go

@@ -394,6 +394,24 @@ func (engine *Engine) Routes() (routes RoutesInfo) {
 	return routes
 }
 
+// Routes returns a slice of registered routes, including some useful information, such as:
+// the http method, path and the handler name.
+func (engine *Engine) Route(handler HandlerFunc) (route RouteInfo, ok bool) {
+	handlerName := nameOfFunction(handler)
+	routes := RoutesInfo{}
+	for _, tree := range engine.trees {
+		routes = iterate("", tree.method, routes, tree.root)
+
+		for _, route := range routes {
+			if route.Handler == handlerName {
+				return route, true
+			}
+		}
+	}
+
+	return RouteInfo{}, false
+}
+
 func iterate(path, method string, routes RoutesInfo, root *node) RoutesInfo {
 	path += root.path
 	if len(root.handlers) > 0 {
@@ -687,6 +705,43 @@ func (engine *Engine) HandleContext(c *Context) {
 	c.handlers = oldHandlers
 }
 
+// PathFor returns the path registered for the specified handler function.
+// Route values are passed pair-wise as key value.
+func (engine *Engine) PathFor(handler HandlerFunc, values ...interface{}) string {
+	route, ok := engine.Route(handler)
+
+	if !ok || len(route.Path) == 0 || len(values)%2 != 0 {
+		return ""
+	}
+
+	url := route.Path
+	params := make(map[string]string)
+	if len(values) > 0 {
+		key := ""
+		for k, v := range values {
+			if k%2 == 0 {
+				key = fmt.Sprint(v)
+			} else {
+				params[key] = fmt.Sprint(v)
+			}
+		}
+	}
+	urls := strings.Split(url, "/")
+	for _, v := range urls {
+		if v == "" {
+			continue
+		}
+		if v[0:1] == ":" {
+			if u, ok := params[v]; ok {
+				delete(params, v)
+				url = strings.Replace(url, v, u, 1)
+			}
+		}
+	}
+
+	return url + toQuerystring(params)
+}
+
 func (engine *Engine) handleHTTPRequest(c *Context) {
 	httpMethod := c.Request.Method
 	rPath := c.Request.URL.Path
@@ -830,3 +885,14 @@ func redirectRequest(c *Context) {
 	http.Redirect(c.Writer, req, rURL, code)
 	c.writermem.WriteHeaderNow()
 }
+
+func toQuerystring(params map[string]string) string {
+	if len(params) == 0 {
+		return ""
+	}
+	u := "?"
+	for k, v := range params {
+		u += k + "=" + v + "&"
+	}
+	return strings.TrimRight(u, "&")
+}

gin_test.go

@@ -874,6 +874,25 @@ func TestPrepareTrustedCIRDsWith(t *testing.T) {
 	}
 }
 
+func TestPathFor(t *testing.T) {
+	r := New()
+
+	getIndex := func(c *Context) {}
+	r.GET("/", getIndex)
+
+	users := r.Group("/users")
+
+	postUser := func(c *Context) {}
+	users.POST("", postUser)
+
+	getUser := func(c *Context) {}
+	users.GET("/:name", getUser)
+
+	assert.Equal(t, "/", r.PathFor(getIndex))
+	assert.Equal(t, "/users", r.PathFor(postUser))
+	assert.Equal(t, "/users/gopher", r.PathFor(getUser, ":name", "gopher"))
+}
+
 func parseCIDR(cidr string) *net.IPNet {
 	_, parsedCIDR, err := net.ParseCIDR(cidr)
 	if err != nil {

recovery.go

@@ -68,6 +68,9 @@ func CustomRecoveryWithWriter(out io.Writer, handle RecoveryFunc) HandlerFunc {
 						}
 					}
 				}
+				if e, ok := err.(error); ok && errors.Is(e, http.ErrAbortHandler) {
+					brokenPipe = true
+				}
 				if logger != nil {
 					const stackSkip = 3
 					if brokenPipe {

recovery_test.go

@@ -142,6 +142,30 @@ func TestPanicWithBrokenPipe(t *testing.T) {
 	}
 }
 
+// TestPanicWithAbortHandler asserts that recovery handles http.ErrAbortHandler as broken pipe
+func TestPanicWithAbortHandler(t *testing.T) {
+	const expectCode = 204
+
+	var buf strings.Builder
+	router := New()
+	router.Use(RecoveryWithWriter(&buf))
+	router.GET("/recovery", func(c *Context) {
+		// Start writing response
+		c.Header("X-Test", "Value")
+		c.Status(expectCode)
+
+		// Panic with ErrAbortHandler which should be treated as broken pipe
+		panic(http.ErrAbortHandler)
+	})
+	// RUN
+	w := PerformRequest(router, http.MethodGet, "/recovery")
+	// TEST
+	assert.Equal(t, expectCode, w.Code)
+	out := buf.String()
+	assert.Contains(t, out, "net/http: abort Handler")
+	assert.NotContains(t, out, "panic recovered")
+}
+
 func TestCustomRecoveryWithWriter(t *testing.T) {
 	errBuffer := new(strings.Builder)
 	buffer := new(strings.Builder)